In a medium-sized bowl, whisk together the crème fraîche and 1/2 cup of the half and half. Set a fine mesh strainer over the bowl, and set aside.
In a medium saucepan, heat 1 cup of the half and half until steamy and small bubbles appear around the sides of the pan. If you have an instant-read thermometer, have it handy.
Place the egg yolks in a medium bowl set on a damp towel to stabilize it. Add the sugar and salt, whisking to combine. Whisking constantly with one hand, pour the hot dairy very slowly into the yolks. (This is called tempering, and prevents the yolks from scrambling from the heat of the dairy.) Pour the mixture back into the pot and set over a low flame. Cook, stirring constantly with a heat-proof silicone spatula, scraping the sides and bottom of the pot, until the custard just begins to 'stick' (or form a thickened filon the bottom of the pot (you may have to tilt the pan to see it), or registers 170º on an instant-read thermometer, 3-5 minutes. Don't let the mixture boil.
Immediately pour the custard through the strainer and into the container of cold cream and half and half. Give the mixture a stir, and chill until very cold, at least 4 hours, and preferably overnight.
Place the ice cream base in the freezer for 30 minutes to get it really cold, stirring it twice during this time. Churn in an ice cream maker. Scrape the ice cream into a chilled container, and 'cure' in the freezer for at least 2 hours for a firmer consistency.
Homemade ice cream is best eaten within the first few days of being made, but will keep for a month or two in the freezer. To prevent crystallization, store the ice cream with a piece of parchment paper pressed directly onto the surface of the ice cream, and store in an airtight container.
Serve this tangy, rich ice cream over any warm fruit dessert, such as Blackberry Balsamic Crisps.You can make your own crème fraîche by stirring 1 tablespoon buttermilk (or crème fraîche) into 1 cup of heavy cream. Cover and let stand at room temperature for 12-24 hours, until thickened, stirring two or three times to prevent a crust of cream from forming on the top. Store in the refrigerator for up to a week.Save the egg whites for making financiers, pistachio chocolate torte, or macaroons. They will keep in the fridge for up to a week, or in the freezer for several months.Nutritional values are based on one of eight servings.